There are many reasons why it may be desirable to return to a previous operating state on a computer system. For example, after a new software package is installed, it may become apparent that the new software conflicts with other software that already resides on the system. The solution provided by industry is to restore the system to its previous state as of a particular time.
For example, when using the Linux® RPM package manager (originally Red Hat Package Manager, abbreviated RPM) to upgrade a computer system, a group of several software packages may be installed at once, or over time. It may turn out that one of the packages, perhaps installed in the middle of the group with respect to time, leaves the system or some of its components, in an unusable state. If this becomes apparent after several other packages are installed, existing solutions permit rolling the system back to its state before the offending package was installed. However, this activity removes packages that were subsequently installed—perhaps packages that operate with no problems, leading to extra work on the system administrator's part, since packages that function properly will likely be re-installed after the rollback is complete.